Refactor of Histogram related code

net/disk_cache/stats_histogram.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/disk_cache/stats_histogram.h"
 
 #include "base/debug/leak_annotations.h"
 #include "base/logging.h"
 #include "base/metrics/statistics_recorder.h"
 #include "net/disk_cache/stats.h"
@@ skipping 15 matching lines @@
 StatsHistogram* StatsHistogram::FactoryGet(const std::string& name) {
   Sample minimum = 1;
   Sample maximum = disk_cache::Stats::kDataSizesLength - 1;
   size_t bucket_count = disk_cache::Stats::kDataSizesLength;
 
   Histogram* histogram = StatisticsRecorder::FindHistogram(name);
   if (!histogram) {
     // To avoid racy destruction at shutdown, the following will be leaked.
     StatsHistogram* stats_histogram =
         new StatsHistogram(name, minimum, maximum, bucket_count);
-    stats_histogram->InitializeBucketRange();
     stats_histogram->SetFlags(kUmaTargetedHistogramFlag);
     histogram = StatisticsRecorder::RegisterOrDeleteDuplicate(stats_histogram);
   }
 
   DCHECK(HISTOGRAM == histogram->histogram_type());
-  DCHECK(histogram->HasConstructorArguments(minimum, maximum, bucket_count));
+  DCHECK(histogram->HasConstructionArguments(minimum, maximum, bucket_count));
 
   // We're preparing for an otherwise unsafe upcast by ensuring we have the
   // proper class type.
   StatsHistogram* return_histogram = static_cast<StatsHistogram*>(histogram);
-  // Validate upcast by seeing that we're probably providing the checksum.
-  CHECK_EQ(return_histogram->StatsHistogram::CalculateRangeChecksum(),
-           return_histogram->CalculateRangeChecksum());
   return return_histogram;
 }
 
 bool StatsHistogram::Init(const Stats* stats) {
   DCHECK(stats);
   if (stats_)
     return false;
 
   // We support statistics report for only one cache.
   init_ = true;
@@ skipping 20 matching lines @@
   // Only report UMA data once.
   StatsHistogram* mutable_me = const_cast<StatsHistogram*>(this);
   mutable_me->ClearFlags(kUmaTargetedHistogramFlag);
 }
 
 Histogram::Inconsistencies StatsHistogram::FindCorruption(
     const SampleSet& snapshot) const {
   return NO_INCONSISTENCIES;  // This class won't monitor inconsistencies.
 }
 
-uint32 StatsHistogram::CalculateRangeChecksum() const {
-  // We don't calculate checksums, so at least establish a unique constant.
-  const uint32 kStatsHistogramChecksum = 0x0cecce;
-  return kStatsHistogramChecksum;
-}
-
 }  // namespace disk_cache